This tool generates standard asymmetric key pairs in SPKI (public) and PKCS#8 (private) PEM plus JWK &mdash; the encodings used by Web Crypto, OpenSSL and JOSE/JWT. It does not build the OpenPGP packet format: there is no user-ID, no expiry or subkeys, no ASCII-armored <code>.asc</code> block and no web of trust, so you cannot import these into GnuPG / Kleopatra, Mailvelope or a mail plugin for PGP email. For true end-to-end encrypted email or file signing with PGP, use GnuPG (gpg), Kleopatra, Mailvelope or Proton Mail. Use this tool for app-level crypto: JWT/JWS signing keys, JWE, TLS/mTLS experiments, ECDH/X25519 key agreement, SSH-style identities and learning how the algorithms differ.

Every key pair is minted on your device by the browser&rsquo;s native Web Crypto API (crypto.subtle.generateKey), which draws its randomness from the operating-system CSPRNG &mdash; never Math.random. The public key, private key, PEM, JWK and SHA-256 fingerprint are all computed locally; there is no fetch, no upload, no logging and no CDN in the crypto path, and even the Ed25519 fallback library is bundled locally rather than loaded from a network. Closing the tab discards every key from memory, and the tool works offline once cached. The only optional network use anywhere on the site is consent-gated ads, which never see your keys.

For new work, Ed25519 (signing) and X25519 (key agreement) are the modern recommendation &mdash; tiny 32-byte keys, fast, and safe by default. ECDSA and ECDH over P-256/P-384/P-521 are compact and widely supported (JWT ES256, TLS, ECDH-ES). RSA is the most universally compatible (JWT RS256, legacy systems) but larger and slower: if you use it, 2048-bit is today&rsquo;s minimum, 3072-bit or more is recommended for long-term keys, and RSA-PSS / RSA-OAEP are preferred over the older PKCS#1 v1.5 schemes. Signing keys prove authenticity; encryption / key-agreement keys protect data &mdash; a key is generated for one job, so pick the purpose first.

The public key is exported as SubjectPublicKeyInfo (SPKI) PEM and JWK; the private key as PKCS#8 PEM and JWK; and a SHA-256 fingerprint of the SPKI DER is shown as both OpenSSH-style SHA256:base64 and colon-separated hex. The private-key panel is warning-styled and blurred until you reveal it so you do not leak it by accident. Because the PKCS#8 export is unencrypted, add a passphrase with your own tooling (for example <code>openssl pkcs8 -topk8 -v2 aes-256-cbc</code>) before storing it, keep it in a secrets manager, and never paste it into a chat, a commit or a screenshot. For production or long-term keys, generate them in vetted tooling or an HSM / KMS so the private key never touches a browser.